Born at Littlebourne, Kent, on 25 May 1693, he was the eldest son of John Denne, woodreeve to the see of Canterbury.
[1][2] Denne was ordained in 1716, and was presented to the perpetual curacy of St Benedict's Church, Cambridge.
He became rector of Norton-by-Daventry, Northamptonshire, in 1721, exchanging the living in 1723 for the vicarage of St Leonard's, Shoreditch.
He arranged and bound up the archives of Rochester Cathedral and the Acts of the Courts of the Bishop and Archdeacon.
He also made some collections for the history of the cathedral, and collated Thomas Hearne's edition of the Textus Roffensis with the original at Rochester.
[1] Denne married in 1724 Susannah, youngest daughter of Samuel Bradford, bishop of Rochester, to whom he was for many years domestic chaplain.